Search results for "numerical [methods]"

Rock decay phenomena and collapse processes in the “Latomiae del Paradiso” in Syracuse (Sicily)

2014

The Latomiae (origin: Greek latomia, from laas, las stone plus –tomia tomy ) del Paradiso in Syracuse are Magna Graecia rock quarries, located in the coastal areas of Southern Italy and internationally renowned for their impressive environment. The few historical technical records do not help clarify the events that led to their current configuration since a series of instability phenomena occurred due to decay processes over time. Through a geotechnical back-analysis, this work highlights the failure phenomena, which may have led to the current configuration of the easterly side of the Latomiae del Paradiso. The back-analysis process was carried out by means of numerical modelling, support…

RELATIVISTIC COMPRESSION AND EXPANSION OF EXPERIENTIAL TIME IN THE LEFT AND RIGHT SPACE

2007

Time, space and numbers are closely linked in the physical world. However, the relativistic-like effects on time perception of spatial and magnitude factors remain poorly investigated. Here we wanted to investigate whether duration judgments of digit visual stimuli are biased depending on the side of space where the stimuli are presented and on the magnitude of the stimulus itself. Different groups of healthy subjects performed duration judgment tasks on various types of visual stimuli. In the first two experiments visual stimuli were constituted by digit pairs (1 and 9), presented in the centre of the screen or in the right and left space. In a third experiment visual stimuli were constitu…

Modeling Atmospheric Turbulence via Rapid Distortion Theory: Spectral Tensor of Velocity and Buoyancy

2017

Abstract A spectral tensor model is presented for turbulent fluctuations of wind velocity components and temperature, assuming uniform vertical gradients in mean temperature and mean wind speed. The model is built upon rapid distortion theory (RDT) following studies by Mann and by Hanazaki and Hunt, using the eddy lifetime parameterization of Mann to make the model stationary. The buoyant spectral tensor model is driven via five parameters: the viscous dissipation rate ε, length scale of energy-containing eddies L, a turbulence anisotropy parameter , gradient Richardson number (Ri) representing the local atmospheric stability, and the rate of destruction of temperature variance . Model outp…

Time-series analyses of species richness and relative abundances at the local scale: some methodological advices to secure the relevance of interpret…

2020

Numerical and experimental study of liquid metal stirring by rotating permanent magnets

2018

In this work, we study liquid gallium stirring by rotating permanent magnets. We demonstrate possibility of easily creating different flow patterns by rotating permanent magnets, which can be industrially important for controlling heat and mass transfer processes in the system. Unlike the typical approach of simulating magnet rotation as a transient problem and time-averaging the Lorentz forces, we solve the magnet rotation as a harmonic (frequency domain) problem, which leads to forces equal to time-averaged ones and decreases the simulation time considerably. Numerical results are validated using qualitative flow structure results from the neutron radiography visualization of tracer parti…

The finite element method for the mechanically-based model of non-local continuum

2011

In this paper the finite element method (FEM) for the mechanically based non-local elastic continuum model is proposed. In such a model each volume element of the domain is considered mutually interacting with the others, beside classical interactions involved by the Cauchy stress field, by means of central body forces that are monotonically decreasing with their inter-distance and proportional to the product of the interacting volume elements. The constitutive relations of the long-range interactions involve the product of the relative displacement of the centroids of volume elements by a proper, distance-decaying function, which accounts for the decrement of the long-range interactions as…

Cognitive predictors of single-digit and procedural calculation skills and their covariation with reading skill.

2006

Abstract This study examined the extent to which children’s cognitive abilities in kindergarten and their mothers’ education predict their single-digit and procedural calculation skills and the covariance of these with reading skill in Grade 4. In kindergarten, we assessed children’s (N = 178) basic number skills, linguistic skills, and visual attention. In Grade 4, we assessed their calculation and reading skills. Data on children’s cognitive ability at 5 years of age and their mothers’ level of education were also collected. The results showed that both of the core components of calculation, single-digit and procedural calculation, as well as their covariance with reading, were predicted …

A robust and efficient method for obtaining the complex modes in inhomogeneously filled waveguides

2003

In this paper, we present a computational simulation of the complex wave propagation in inhomogeneously filled waveguides with lossless and lossy dielectrics. We use a biorthonormal-basis method as a numerical technique. The behavior of complex modes in different waveguides whose characterization with other methods involves some difficulties is analyzed. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 37: 218–222, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10875

Association between night-time surgery and occurrence of intraoperative adverse events and postoperative pulmonary complications

2019

WOS: 000458513600019

Numerical Model for Shape Memory Alloy Actuators

2008

In order to realize a control system for Shape Memory Alloy (SMA) actuators, that ensure high displacement precisions, a numerical model that simulates SMA wire behavior subjected to thermo-mechanical actions, up to high number of cycles, has been set up. In particular, the constitutive model of Brinson, 1993,[1] coupled by a suitable kinetic low has been used. Beginning from such model, some corrections have been performed to take into account the deviations, in term of characteristic temperatures and mechanical responds, due to a numerous thermo-mechanical cycles. Furthermore, in order to complete and check the numerical model, experimental tests have been performed; initially the employe…